Scaffolding clamp



'Nov. 5, 1935. I I 's. F. BURTON ,ET AL 2,020,102

SCAFFOLDING CLAMP Filed June.l4, 1935 INVENTORS'.

Snowew FRRNH Bun-row HLBERT Low:

I 1 "YTORN YS Patented Nov. 5, 1935 UNITED STATES PATENT "TI SCAFFOLDING CLAMP Application June 14, 1935, Serial No. 26,570 In Great Britain February 7, 1934 12 Claims.

invention relates to clamps for attaching a pair of scaffolding tubes, poles, or other members together in transverse relationship, and refers to that kind of clamp which has a central 5,; block for engagement between the two scaffolding members to be coupled together, and two caps disposed on opposite sides of said block hinged thereto and adapted to engage the outer sides of the members, means being provided for drawing the 10 caps towards the central block into gripping engagement with the scaffolding members to clamp the latter thereto.

In clamps of this kind, the central block is usually provided with seating portions which are 15 adapted partially to embrace the two scaffolding members and to locate them in transverse relationship, while the clamping caps may also be curved to embrace the outer sides of the members. In clamps of this kindas hitherto made, the 20 caps are formed as parti-cylindrical members hinged at one edge to the central block, the outer edge being acted upon centrally by a securing screw or bolt associated therewith; two securing screws or bolts being thus employed, one screw 25 ,or bolt being used for securing each of the caps in gripping engagement with the scaffolding member. 7

- Further, with existing forms of clamps of the kind enumerated above the clamping pressures U applied to the two scaffolding members are equal, whereas under certain conditions, such as when the clamp is employed tosecure'a ledger or other rlorizontalmember to a standard or upright, the force tending to displace the clamp will actu- 35 ally be much greater in one direction, (i. e. longitudinally of the standard) than in another direction perpendicular thereto.

One of the objects of the present invention is to provide a simplified construction wherem a single 40 screw or bo l-t may be employed for drawing the two caps into engagement with their respective scaffolding members.

.A further object of this invention is to provide an improved-construction of, clamp Which, with- 45 out involving an increased number of parts, will enable a greater pressure to be applied to one of the members to be coupled than to the other. Aclamp constructed as hereinafterdescribed can thus be attached to a standard much more se- 50, curely than has been possible hitherto, and this without in any way affecting the clamping pressure applied to the ledger.

.Other objects will become apparent from the following-description of the invention, 55 Referring to the drawing:-

Figure l is a perspective View of one form of scaffolding clamp constructed in accordance with the invention.

7 Figure 2 is a side elevation of the clamp show ing the method of coupling together a pair of ,51 scaffolding members, and

Figure 3 is a view similar to Figure 1, but with the clamp in an inverted position.

In the construction illustrated, the clamp includes a central block iii adapted to be engaged between the scaffolding members which are to be coupled together, this block being in the shape of a cross and formed on opposite sides with two parti-cylindrical seatings H, E2, in perpendicular relationship and adapted to receive the scaffolding members aforesaid. When the clamp is employed for securing a ledger, putlog, or other horizontal member to a standard or upright of the scaffold ing, with the axes of the tubular or other members at right angles to one another, these seatings ll, [2, engage adjacent sides of the standard it and the horizontal member M respectively, as shown in Figure 2.

The outer sides .of the coupled members I3, M are adapted to be engaged by clamping caps I5,

I6 respectively, these latter being of parti-cylindrical form and hinged at one edge to the central block l0. Preferably the edge of each can is of bulbous shape, as at H, and has its central portion cutaway to receive a lug 18 formed at the back of one ofthe seatings ll, l2, a pin 99 .extending through the bulbous edge H of the cap and serving to connect hingedly the latter to the lug l8. The-axes of the hinge pins l9 are, of course, parallel to those of the coupled members when the latter are in position.

At the edge opposite to the hinge pin !9, each clamping cap l5, I6 is provided with a laterally extending ear 20, 20arespectively which is disposed atone end of the cap, a primary securing screw 2|, and a further securing screw 2Ia extending through the ears 28, 20a respectively and in the direction of the other cap.

Conveniently, the screw 2! is adapted to engage a threaded hole in a lug or web 22 formed on the central block ill at one side of the seating l2. 'Ihe'securing screw 25a carried by the cap l6, however, extends past the block ill, parallel to the other screw. but on the opposite side of the seating l2, and engages with an ear 23 formed, not on the block I0, but on the cap I5. This ear 23 is disposed at the end of the cap l5 remote fromthe aforementioned car 20 thereon, and preferably it is formed with a projecting boss 24 in which the screw threaded hole is pro- 5 vided so that the two securing screws 2| and 2 la may be made of equal length.

In order that the securing screws may be inseparably associated with the ears 20 and 2011, each of the latter is provided with a hole 25 of sufiicient diameter to allow the threaded portion 26 of the screw stem to be passed therethrough, a washer 27 of the same internal diameter being slipped over the threads and then diametrically compressed so as to engage with a reduced part of the screw stem as shown in Figure 2. This washer 21 is accommodated in a recess 28 formed in the inner face of each car.

In assembling a scaffold with the aid of the improved clamp, the securing screws 2| and 2la are first disengaged from the ears 2 0 and 20a and the cap I5'is hinged outwardly to enable the seating II on the central block II! to be placed against a standard at the desired position, and is then swung back so as to bear on the outer side of the standard, the screw 2| thereon being afterwards engaged with the lug 22 on the block ID and tightened up so as to secure the clamp in position.

To facilitate the insertion in the clamp of a horizontal member such as a ledger, the device is preferably secured to the standard in the position shown in Figure 1, with the hinge pin l9 at the lower edge of the cap 16. In order to prevent the latter swinging down too far, it may be formed with an integral abutment 28 as shown which engages the end of the lug l8 on the block ID and serves to retain the cap in a substantially horizontal position so that it serves as a rest when the ledger or other member is lifted into place.

The cap I6 is then raised so as to bring the ledger up against the seating l2, and the securing screw 2 la thereon is engaged with the boss 24 projecting from the other cap 15 and is tightened up. This, it will be seen, not only clamps the ledger in place, but also applies additional constrictive pressure to the standard. The single grip afforded by the clamping cap I6 is amply sufficient to secure the ledger against endwlse movement, Whilst the-double grip on the standard which is obtained by the interconnection of the caps I5, l6, gives adequate security against. downward movement of the clamp under the weight of workmen, platforms, and building materials which the scaffold may be required to support.

Thus, by providing two screws or other securing means for maintaining one of the caps in gripping engagement with its scaffolding member pressure is applied to the cap at two positions spaced longitudinally of the scaffolding member and the clamping effect of this is increased without the necessity for additional parts, pressure being applied at a single position to the other cap so that a triple pressure or grip is applied to the two caps as a whole and exertedthereby. on to the scafiolding members which are coupled together by the clamp. 7

Further, on applying increased load to the horizontal member l4 tending to move this longitudinally of the standard l3 in a downward di rection, a proportion of this load is transmitted to the cap l6 causing it to pivot in an outward direction away from the central block, so that additional pressure is transmitted through the screw 2la to the cap l5 engaging the standard causing it to grip the latter more tightly with a resultthat any downward movement, of the, scafiolding clamp on the standard l3 as a result a tween ears provided on the block and cap respecof the increased load applied to the member I! is prevented.

Instead of securing screws being carried by the clamping caps in the manner shown, the caps may be tightened against the scaffolding mem- 5 bers by means of bolts, the head of one of such bolts engaging the central block In whilst the head of the other engages the cap [5. For instance, the heads of the bolts may be hinged betively, the axis of the hinge in each case being parallel to that of the cap with which the nut on the bolt engages, and the stems of the bolts may be adapted to enter slots or between pairs of ears provided at the free edges of said caps.

What We claim then is:

1. A clamp for securing a pair of members in assembled relationship comprising in combination a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed on two sides of said block, means connecting said caps to said block, said caps being adapted each for engagement with a member to clamp the latter to the block, pri* mary securing means for fastening one of the caps to the block, said securing means being adapted to apply clamping pressure to said cap and draw it into engagement with one member to secure the clamp in position thereon, further securing means adapted to draw the other cap into gripping engagement with the other member, said further securing means being adapted also to apply additional clamping pressure to said first-mentioned cap.

2. A clamp for securing a pair of scaffolding members in transverse relationship comprising in combination a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly 40 thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, primary securing means for fastening one of the caps to the block, said securing means being adapted to apply clamping 45 pressure to said cap and draw it into engagement with its scaffolding member to secure the clamp in position thereon, further securing means adapted, to draw the other cap into gripping engagement with its corresponding scaffolding member, and said further securing means being adapted also to apply additional clamping pressure to said first-mentioned cap.

3. A clamp for securing a pair of scaffolding members in transverse relationship comprising in combination, a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, a pair of securing means adapted to apply clamping pressure to one of said caps and maintain it in gripping engagement with a scaffolding member, said securing means being arranged to apply the clamping pressure at positions spaced longitudinally of the scaffolding member, one of said securing means being adapted also to apply clamping pressure to the other cap to maintain it in gripping engagement with its corresponding scaffolding member, and said securing means being adapted collectively to apply to said first-mentioned cap a clamping pressure greater than that applied to said latter cap.

4; A clamp forsecuring a pair of members in assembled relationship comprising in combina tion, a block for disposition between the two inembersand adapted for engagement therewith, a pair-of caps disposed on two sides of said block, means connecting said caps to said block, said caps being adapted each for engagement with a member to clamp the latter to the block, a primary threaded securing member forfastening one of the caps to the block, said securing member being-adapted to apply clamping pressure to said cap and draw it into engagement with one member to secure the clamp in position thereon, a further threaded securing member adapted to draw the other cap into gripping engagement withits corresponding member, said further securing member being adapted also to apply additional clamping pressure to said first-mentioned cap.

5. A clamp for securing a pair of scaffolding members in transverse relationship comprising in' combination, a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, a primary threaded securing member for fastening one of the caps to theiblock, said securing member being adapted to apply clamping pressure to said cap and draw it into engagement with its scaffolding member to secure the clamp in position thereon, a further threaded securing member adapted to draw the other cap into. gripping engagement with its corresponding scaffolding member, and said further securing member being adapted also to apply additional clamping pressure to said first-mentioned cap.

6. Aclamp for securing a pair of scaffolding members in transverse relationship comprising in combination, a block fordisposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, a pair of threaded securing members adapted to apply clamping pressure to one of the caps at positions spaced longitudinally of its scaffolding member and to maintain it in gripping engagement with the latter, one of said securing members being adapted to fasten said cap to said block and the other securing member being adapted to fasten the two caps together and to apply clamping pressure to the other cap to maintain it in gripping engagement with its corresponding scaffolding member, and said pair of securing members being adapted together to apply to said firstmentioned cap a clamping pressure substantially greater than that applied by said latter securing member to said latter cap.

7. A clamp for securing a pair of scaffolding members in transverse relationship comprising in combination, a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, a threaded securing member associated with one of the clamping caps and acting at one end thereof, said securing member being adapted for engagement with said block to draw said cap into clamping engagement with its scaffolding member, a further threaded securing member acting upon the other end of said cap, said further seeming member beingassociated with the other cap, and said further securing member being adapted to draw said latter cap into clamping engagement with its corresponding scaffolding member and to apply additional clamping pressure to said first-mentioned cap.

8. A clamp for securing a pair of scaffolding members in transverse relationship comprising in combination a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on oppo-' site sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, one of said caps having an opening, said block having also an opening, each of said openings being internally threaded, a securing screw mounted on said cap and adapted to engage in said opening in the block, and a' further securing screw mounted on the other Iclamping cap adapted for engagement with the opening of said first-mentioned cap.

,9. Aclamp for securing a pair of scaffolding members in transverse relationship comprising in combination a block for disposition between the two' members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scafiolding member to clamp the latter to the block, one of said caps having an opening adjacent one end thereof, a securing screw mounted on said cap adjacent the opposite end thereof, said block having also an opening, each of said openings being internally threaded, said securing screw being adapted to engage in said opening .in the block, a further securing screw mounted on the other clamping cap substantially adjacent one end thereof, and said latter securing screw being adapted for engagement with the opening of said first-mentioned cap.

10. A clamp for securing a pair of scafiolding members of circular cross section in transverse relationship comprising in combination, a block having a pair of recesses of part-circular form disposed transversely to one another and arranged on opposite sides of the block, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, each of said caps being of part-circular shape and adapted each to engage a scaffolding member and maintain it in one of said recesses in gripping engagement with said block, each of said caps having a securing screw mounted adjacent the free edge thereof, one of said caps having an opening, said block having also an opening, each of said openings being internally threaded, the securing screw of one of said caps being adapted for engagement with the opening of said other cap, and the other securing screw being adapted for engagement with the opening of said block.

11. A. clamp for securing a pair of scaffolding members in transverse relationship comprising in combination, a block for disposition between the two members and adapted for engagement therewith, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps being adapted each for engagement with a scaffolding member to clamp the latter to the block, each of said caps having an aperture, a securing screw extending through each of said apertures, one of said caps having an opening, said block having also an opening, each of said openings being internally threaded,

. each of said securing screws having screw threads engageable with said threaded openings, the securing screw of one of said caps being adapted for engagement with the opening of said other cap, and the other securing screw being adapted. for engagement with the opening of said block, each of said screws having an unthreaded portion intermediate the ends thereof, said unthreaded portions having a diameter less than that of the threads of said screws, a washer mounted on the Lmthreaded portion of each of said screws intermediate the ends of the shank thereof, each of said washers being adapted for engagement with edge portions of said apertures, and said washers having each an internal diameter less than that of the threads of the associated screw.

12. A clamp for securing a pair of scafiolding members of circular cross-section in transverse relationship comprising in combination, a block having a pair of recesses of part-circular form disposed transversely to one another and. arranged on opposite sides of the block, a pair of caps disposed each on opposite sides of said block and connected hingedly thereto, said caps and said recesses being disposed at right angles to one another respectively, each of said caps being of part-circular shape-and adapted each to engage a scaffolding member and maintain it in one of said recesses in gripping engagement with said block, each of said caps having an aperture, adjacent the free edge thereof, each of said apertures being disposed at one end of its respective cap, a securing screw extending through each of said apertures, one of said caps having an opening disposed at the end thereof remote from its aperture, said block having also an opening, each of said openings being internally threaded each of said securing screws having screw threads engageable with said threaded ope'nings, the securing screw of one of said caps being adapted for engagement with the opening of said other cap, the other securing screw being adapted for engagement with the opening of said block, each of said screws having an unthreaded portion intermediate the ends thereof, said unthreaded portions having a diameter less than that of the threads of said screws, a washer mounted on the unthreaded portion of each of said screws intermediate the ends of the shank thereof, each of said washers being adapted for engagement with edge portions of said apertures, and said washers having each an internal diameter less than that of the threads of the associated screw.

SIDNEY FRANK BURTON. ALBERT LOWE. 

